.button {
    -fx-min-width: 20px;
    -fx-min-height: 20px;
    -fx-max-width: 20px;
    -fx-max-height: 20px;
    -fx-pref-height: 20px;
    -fx-pref-width: 20px;
    -fx-background-color: rgb(0,0,0);
    -fx-opacity: 0.5;
    -fx-background-radius: 0;
    -fx-background-size: 15px 15px;
    -fx-background-repeat: no-repeat;
    -fx-background-position: center;
}

#refreshBtn {
    -fx-background-image: url(/resource/Images/refresh.png);
}
#settingBtn {
    -fx-background-image: url(/resource/Images/setting.png);
}
